Gas protective mask



Feb. 19, 1929.

B. DRAGER GAS PROTECTIVE MASK Filed 0012 12, 1926 2 Sheets-Sheet l Feb. 19, 1929.

A. B. DRKG ER GAS PROTECTIVE IASK Filed Oct 12, 1926 2 Sheets-Sheet 2 l atented Feb. 19, 1929.

'UNITED STATES PATENT OFFICE.

STAN GE, EXEGUTRIX OF THE ESTATE OF SAID ALEXANDER IDECEASED.

BERNHAB-D DBKGER,

GAS PROTECTIVE MASK.

Application filed October 12, 1926, Serial No. 141339;, and in Germany November 2, 1925.

Gas protective masks having in the inside an auxiliary mask wh1ch embraces the nose and mouth 'are known. These auxiliary masks do not suificicntly divide the air space within the main mask into two completely separate parts from one another, because to the wall of the auxiliary mask is either attached an inhaling valve or an exhaling valve, which forms a communication between the inner space of the auxiliary mask and the remaining inner space of the main mask. When the auxiliary mask is provided with an inhaling valve, the exhaled air is cut oil from the air space of the main mask only by the auxiliary mask, which however with the object of keeping the mask window clean'is rinsed by the dry fresh inhaling air. If the wall of the auxiliary mask carries an exhaling valve, only the inhaled air is prevented from entering the inner space of the main mask, while the exhaled air is allowed to enter the main -mask with the view of producing an overpressure within the main mask to prevent the entrance of noxious gases.

The gas protective mask according to the invention ditters from the known constructions in that the auxiliary mask is, with the exception of the orifice for connecting the breathing hose or the breathing hoses, so closed up that the inhaled air as well as the exhaled air is prevented from entering the space between the main mask and the auxiliary mask. The result of this arrangement is an essential reduction of the work the lungs have to perform, because at that place where the breathing apparatus is connected to the breathing paths of the carrier of the apparatus, there is no or at least only a very slight air space that could act similar to a bellows or an air chamber of a ump, the filling and emptying of which won d increase the labor exerted b the lungs of the wearer. The new gas mask therefore is a medium between an exhalin mask and a breathing mouth-piece, the a vantages of both being combined and the disadvantages of both bein avoided.- The work the lungs have to per orm in connection with such mask is reduced to such an extent which approximately is inherent to a breathing mouthpiece. At the same time it gives the advantage of protection as a normal mask and avoids the drawbacks which are connected with a pure mouth-piece breathing.

For the proper fit of the main and of the auxiliary mask to or in front of the face of the wearer a chinrest, crossin the lower part of the main m'ask and ma e of a strip of fabric which is connected also to the lower rear rim of the auxiliary mask, is of great mask the said strip of fabric, which is preferably attached to the jointor closin -rim of the main mask, also preferably ma e of a pliable fabric, bears in front against the chin and thus limits the applying movement of the mask on or against the face and ensures in this manner the proper or snug fit of the main mask. In applying the main mask the auxiliary mask which covers the nose and the mouth, will be compressed toimportance. In applying the gas-protective wards the place of connection of the breathing hose, whereby the lower part of the rear rim of the auxiliarymask will be held up and tight by the strip of fabric formin the chin rest, so that also the auxiliary mas will be given the proper tight fit around the mouth and nose. Because of the fact that the auxiliar mask prevents the entrance of of warm ex ialed air into the dead space of the main mask it also acts to protect the windows of the mask from being steamed. In order to allow the nose while breathing to freely expand without having the sides or wings of the nose coming into inconvenient contact with the walls of the auxiliary mask these are made at this point in cupshaped form or are provided with pockets.

Fig. 1 of the drawing is a rear view of a breathing mask provided with an auxiliary mask and a chin test.

Fig. 2 is a section drawn to the line A-B of Fig. 1.

Fig. 3 is a perspective view of a spring arrangement for the inner mask on a somewith each other preferabl by a rigid member e. g. by a common bri ge ring 0, through the medium of which the mask may also be connected in known manner with the usual breathing hose, not shown. The strip of fabric d forming the chin rest is-attached with both ends at opposite points to the contact or closing rim a of the main mask a. Straps connected to the outer mask tend to pull the lower part of the same backwards thereby pressing the strip at on the front of the chin and keeping the strip in a definite position on the chin, in which it extends horizontally across the same. The flapshaped connecting part 1) extends from the lower section of the rim of the inner mask 6 upwards to the strip 07 and is attached thereto by cementing or otherwise. The chin rest d connected with the main mask may also be made integral with the connecting part b and the part b integral with the inner mask 6.

In order to obtain a tight contract of-the auxiliary mask at both sides thereof resilient means, i. e. springs f, may be provided which are inserted between the rigid bridge ring 0. Fig. 3, and the contact rim of the auxiliary mask, and thus hold the latter towards the face. For better distributing the pressure of the spring the contact rim of the auxiliary mask may be stiffened by a wire or wire ring e suitably bent to shape.

The construction shown in Figs. 4 and 5 differs from that described above in the peculiar shape of the inner, auxiliary mask inasmuch as a special space is created for the sides and wings of the nose of the wearer to avoid, as has been explained above, inconvenient contact with the walls of the auxiliary mask while breathing. This object in view, the side walls of the auxiliary mask are provided with a cup-shaped or bulged out part towards the outside or a pocket I) which afford the necessa free space for the wings of the nose and t us enable them to expand while breathing.

I claim 1. A gas protective device comprising an outer gas mask adapted to fit with its rim to the periphery of the face, an inner gas mask of pliable material adapted to fit with its rim to the face along a contact line surrounding nose, mouth and chin, an opening in the inner mask forming a passage for the breathing air, a separate strip attached at opposite points to the first named rim and extending horizontally across the front of the chin, and a connecting element extending from the lower portion of the second named rim upwards to said strip adapted to keep said second named rim in close contact with the face.

2. A gas protective device comprising an outer gas mask adapted to fit with its rim to the periphery of the face, means to keep said rim in tight contact with the face, a rigid member connected to the outer mask, an inner gas mask of pliable material adapted to fit with its rim to the face along a contact line surrounding nose and mouth and connected to the rigid member, stiffening means attached to the inner gas mask and stiffening the rim thereof, and resilient means inserted between said rigid member and said stiffening means and tending to keep the above mentioned rim in tight contact with the face.

3. The combination claimed in claim 2 in which the stiffening means comprise a wire extending along the rim of said inner mask.

4. A gas protective device comprising an outer gas mask fitting with its rim to the periphery of the face, means to keep said rim in tight contact with the face, a rigid member connected to the outer mask, an inner gas mask of pliable material fitting with its rim to the face along a contact line surroundin nose and mouth and connected to the rigi member, stiffening means attached to the inner as mask and stiffening the rim thereof, resllient means inserted between said rigid part and said stiffening means and tending to keep the above mentioned rim in tight contact with the face, a chin rest connected to the rim of the outer mask so as to assume a definite position on the chin, and connecting means between said rest and the lower section of the rim of the inner mask adapted to keep said rim in'close ALEXANDER taxman union. 

